1. Field
The described technology relates generally to an organic light emitting diode (OLED) display.
2. Description of the Related Technology
An organic light emitting diode (OLED) display includes two electrodes and an organic emission layer disposed between the two electrodes. Electrons injected from one electrode and holes injected from the other electrode are combined in the organic emission layer such that excitons are formed, and light is emitted by energy generated from the excitons.
The organic light emitting diode (OLED) display includes a plurality of pixels including an organic light emitting diode (OLED) as a self-light emitting element, and each pixel includes a plurality of thin film transistors (TFT) and a capacitor to drive the organic light emitting diode (OLED).
The capacitor includes a storage capacitor to store a data signal and a boosting capacitor performing a boosting operation according to a voltage change of a signal line for a further correction of expression of grayscales, and a luminance of the pixel including the storage capacitor and the boosting capacitor is changed according to a capacitance ratio of the two capacitors.
For uniform luminance, the capacitance ratio of the storage capacitor and the boosting capacitor must generally be uniform between a plurality of pixels.
However, the boosting capacitor is typically set to have smaller capacitance than the storage capacitor, and thereby a change amount according to a process distribution is relatively large. A luminance deviation and a color deviation may be generated by the capacitance deviation between the boosting capacitors included in a plurality of pixels.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.